Gamma-ray Burst 050128

(All information courtesy of the instrument teams.)

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Results of Observations

GCN notice #2991
```
TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  2991
SUBJECT: GRB 050128: Swift XRT prompt afterglow position
DATE:    05/01/28 09:17:28 GMT
FROM:    David Burrows at PSU/Swift  
```
L. A. Antonelli (INAF-OAR), S. Campana, G. Tagliaferri, C. Pagani, A. Moretti, P. Romano, G. Chincarini (OAB), P. Giommi (ASI), D. N. Burrows, J. E. Hill, J. A. Kennea, J. Racusin, J. A. Nousek (PSU), J. Osborne, K. Page, M. Goad, A. Beardmore, A. Wells (U. Leicester), K. Mason (MSSL), N. White, N. Gehrels (NASA/GSFC), report on behalf of the Swift XRT team:
The Swift BAT instrument detected an apparent burst at 04:20:04 UT on 2005 January 28. The spacecraft initiated a prompt automated slew and observation sequence. The XRT began taking data on the burst at 2005-01-28 04:23:51 and continued until 2005-01-28 05:55:27. The XRT was in Photon Counting mode performing calibration observations of PG1311+129 when the burst occurred, and continued to collect data in Photon Counting mode during the slew and after settling onto the BAT field. As a result, no prompt XRT position was reported to the ground. However, analysis of the XRT data shows a bright, rapidly fading point source at:
```
RA(J2000): 14 38 17.87
DEC(J2000): -34 45 56.6
```
These positions were processed through the ground pipeline and have an estimated uncertainty of 8 arcseconds, dominated by systematic uncertainties in the XRT boresight, which is not yet fully calibrated. We note, however, that our final position for GRB050126 was 30 arcseconds from the optical candidate (GCN 2985) in spite of our estimated uncertainty of 8 arcseconds.
The XRT count rate is 1.29+/-0.28 c/s (0.5-10 keV) in a 1745 s exposure, which corresponds roughly to a 1 mCrab source.
The XRT is continuing to observe this burst when it is visible to the Swift observatory.
GCN notice #2992
J. Cummings (GSFC), G. Sato (ISAS), L. Antonelli (INAF-OAR), S. Barthelmy, L. Barbier (GSFC), P. Boyd (GSFC-UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (GSFC/UMD), H. Krimm (GSFC/USRA), F. Marshall (GSFC), C. Markwardt (GSFC/UMD), K. McLean (LANL), C. Milvia (ASDC), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC), M. Suzuki (Saitama), J. Tueller (GSFC), S. Zane (MSSL) on behalf of the Swift-BAT team:
At 04:19:54 UT, the Swift Burst Alert Telescope (BAT) triggered and located on-board GRB050128. The spacecraft autonomously slewed to the burst and an x-ray afterglow source was detected by XRT (GCN 2991, Antonelli et al.).
The BAT on-board calculated location is RA,Dec 219.587, -34.762 (J2000) with an uncertainty of 3 arcmin (radius, 3-sigma, including a systematic uncertainty dominated by the GRB being 51 deg off axis). This is 39 arcsec from the XRT position. The lightcurve is multi-peaked with a T90 duration of 13.8 sec. The fluence is 4.5e-6 erg/cm^2 and the peak flux (1 sec interval) is 4.6 ph/cm^2/s in the 15-350 keV band. The spectrum is consistent with a power-law of photon index 1.5 +- 0.05.
GCN notice #2998
S.Maeno,E.Sonoda,Y.Matsuo,M.Yamauchi (University of Miyazaki)
"We have observed the field covering the error box of GRB 050128 (GCN 2992;Swift-BAT Trigger time is 04:19:54 UT) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki.
The observation was started 19:23:52 UT on Jan.28. Observed field of view is 43 arcmin centerd on
```
R.A.=14h 38m 11s
Dec= -34d 42' 34"
```
After co-adding a set of 3 images of 30 sec exposures, we have compared with the USNO A2.0 catalog. Preliminary analysis shows there is no new source brighter than 17.5 mag.
GCN notice #2999
S. Covino, P. Filliatre, P. D'Avanzo, L.A. Antonelli, A. Melandri, V. Testa, G. Chincarini, G. Tagliaferri, F.M. Zerbi, G. Tosti, A. Monfardini, M. Rodono', E. Molinari, F. Vitali, G. Cutispoto, L. Nicastro, E. Palazzi, on behalf of the REM/ROSS team, report:
We imaged the field of GRB050128 (Antonelli, et al., GCN 2991) with the 60cm REM robotic telescope located in La Silla (Chile). Observations were carried out in the V, R, I, z', J, H and K filters, starting on 2005 Jan 28, at 7:10 UT, and ending at 9:45 UT (approximately 3 hours after the burst). Observations were carried out under good seeing conditions (1"). Due to a technical problem only IR images have been analysed.
No new sources have been detected within the XRT error circle (GCN 2991) down to a limiting magnitude of H>17 mag.
We note a source (H = 16.8+/-0.3 mag) at RA= 14:38:18.16, DEC=-34:45:44.7 (J2000) at about 13 arcsec far from the XRT position. At this position a very faint source, close to the detection limit, is present in the optical DSS frame but it is not present in the Infrared DSS frame which is deeper than our image.
Further observations are planned to look for any variability.
This message can be cited.
GCN notice #3001
A. Monfardini (Liverpool), N. Tanvir (Hertfordshire), R. Smith (Liverpool), C. Mottram (Liverpool), D. Carter (Liverpool), C. Mundell (Liverpool), C. Guidorzi (Liverpool), B. Chapman (Hertfordshire), P. O'Brien (Leicester) on behalf of the larger Robonet consortium, report:
"We obtained BVRI images centered on the SWIFT-XRT detection of GRB050128 (GCN 2991; BAT detection: GCN 2992) with the 2-m Faulkes Telescope South on Siding Spring, Australia. Observations started on January 28.658 UT, i.e. 11.455 hours after the GRB. The robotic GRB pipeline did not find any new objects with reference to USNOB, GSC2.3 and 2MASS catalogues.
We report the preliminary R-band limit:
```
Time from GRB   ExpTime    Filter    Limit Mag.
(days)          (s)
-----------------------------------------------
0.477           240         R        ~20.5
-----------------------------------------------
```
The above limit magnitude has been derived by comparison with USNOB catalog and refers to a single out of five 240s exposures. Analysis is in progress on I images (5x300s). Further observations are planned for variability check that requires a comparison image deeper than the DSS-2.
This message can be cited."
GCN notice #3004
A. Melandri, E. Palazzi, L. A. Antonelli, S. Covino, P. D'Avanzo, G. Tagliaferri, G. Chincarini, F. M. Zerbi, G. Tosti, A. Monfardini, N. Masetti, L. Nicastro, G. Cutispoto, E. Molinari, M. Rodono' and F. Vitali on behalf of the REM/ROSS team, report:
"We imaged the field of GRB050128 (Antonelli, et al., GCN 2991) with the 60cm REM robotic telescope located in La Silla (Chile). Optical observations were carried out in V, R, I filters starting on 2005 Jan 28, at 7:10 UT, and ending at 9:45 UT (approximately 3 hours after the burst) . Observations have been partly affected by the presence of the bright Moon close to the field, so only frames with short exposure time can be used. The field was imaged in each filter for a total exposure time of 50s.
No new sources are detected within the XRT error circle (Antonelli et al. GCN 2991) down to a limiting magnitude of V >18.2, R >18.2 and I >17.9.
The source noted in the H band (Covino, et al., GCN 2999) at RA= 14:38:18.16, DEC=-34:45:44.7 (J2000) at about 13 arcsec far from the XRT position is not visible in the optical bands. We derive a 3-sigma upper limit of R > 18.2 at the position of this source.
Further optical-infrared observations with REM are planned to look for any variability.
This message can be cited."
GCN notice #3011
D. A. Frail (NRAO) and A. M. Soderberg (Caltech) report on behalf of the Caltech-NRAO-Carnegie GRB Collaboration:
"We observed the field centered on the XRT position of the Swift burst GRB 050128 (GCN#2991) with the VLA on February 8.53 UT at a frequency of 8.46 GHz. There are no bright radio sources (>150 microJy) within 1 arcminute of the XRT position, and no peak emission above 100 microJy (rms=31 uJy) within the 8-arcsec XRT error circle.
No further observations are planned."
arXiv:1504.02482 putative R-band host detection: z<5.5

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Jochen Greiner, last update: 07-Jul-2015 [Disclaimer]